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In the realm of modern powertrains, the paramount objectives of weight reduction, cost efficiency, and friction optimization drive innovation. By streamlining drive trains through component minimization, the paper introduces a groundbreaking approach: the integration of fuel pump and vacuum pump drive systems into the main camshaft of a two-valve-per-cylinder push-rod actuated 4-cylinder diesel engine. This innovation is poised to concurrently reduce overall weight, lower costs, and minimize drive losses. The proposed integration entails the extension of the camshaft with a tailored slot, accommodating a three-lobed cam composed of advanced materials. This novel camshaft configuration enables the unified propulsion of the oil pump, vacuum pump, fuel pump, and valve train, effectively consolidating functions and components.

Use of Computer Aided Engineering (CAE) tools for virtual validation has become an essential part of every product development process. Using CAE tools, accurate prediction of potential failure locations is possible even before building the proto. This paper presents a detailed case study of virtual validation of Backhoe Loader (BHL) dipper arm using CAE tools (MBD: Multi Body Dynamics and FEA: Finite Element Analysis) and comparison of simulation results with test data. In this paper, we have illustrated the modelling of Backhoe Loader in MSc ADAMS software. The detail ADAMS model was created and validated. The component mass, Center of Gravity (C.G) and Mass Moment of Inertia (MOI) was taken from CAD data. Trenching is simulated by operating the different hydraulic cylinders of the BHL. Loader arm cylinders and stabilizer cylinders are operated to lift the machine tires above the ground level.

Synchronizers are the most critical parts of a manual transmission. There are classical calculations available for the synchronizer design and studies are available for the normal functioning of synchronizer rings which describes how the synchronizer behaves in the event of gear shifting. The objective of this study is to describe the synchronizer behavior when synchronizers are not functional, i.e., in other gear engaged condition and the rings are free. This study describes the failure mechanism of the unused synchronizer rings which are moving freely in the packaging space. The findings of this synchronizer design cannot be limited only for synchronizer performance and standard durability calculations. To ensure proper function of synchronizer rings and to achieve the required life the external parameters like clearances, lubrication, clutch design for dampening torsional vibration from the engine are to be considered.

To meet stringent US EPA - TIER IV final emission norms, the diesel engine manufacturers are using various technology approaches. These approaches are varying from advanced in-cylinder combustion strategies to sophisticated exhaust after-treatment technologies. Generally, the proven technology concepts such as Common Rail System (CRS), efficient Turbocharged-Intercooled (TCI), and controlled-cooled EGR along with DOC-DPF in after treatment are used for emission controls. However, this approach will increase the engine cost in addition to the Packaging challenges for the existing vehicle layouts. This paper describes the successful attempt to meet US EPA TIER IV final (<37 kW power category) emission norms on a 2.7 l, Naturally Aspirated (NA) diesel engine for off-highway application. Use of high pressure CRS system, moderate Excess Air Ratio (λ) and optimum engine swept volume selection helped to retain fuel consumption at par with interim TIER IV engine.

The need for automotive OEMs to manage product complexities and tough time to market in a competitive global industry mandates systems-driven product development process, which combines systems engineering methodology across all development domains with an integrated definition of the product. Businesses unable to adapt quickly lose mind share as well as market share. It is critical to the success of an automotive OEM to apply a consistent process framework based on systems engineering to capture, manage and organize information and knowledge, beginning with the voice of the customer, and continuing through product development, service, support and end-of-life. Systems engineering is important because it effectively nourishes an initial idea into a full system description, with all necessary elements integrated to form a complete product.

In today’s cost-competitive automotive market, use of finite element simulations and optimization tools has become crucial to deliver durable and reliable products. Simulation driven design is the key to reduce number of physical prototypes, design iterations, cost and time to market. However, simulation driven design optimization tools have struggled to find global acceptance and are typically underutilized in many applications; especially in situations where the algorithms have to compete with existing know-how decision making processes. In this study, systematic multi-phase approach for optimization driven design is presented. Approach includes three optimization phases. In first phase, topology optimization is performed on concept BIW design volume to identify critical load paths. Architectural inputs from topology are used to design base CAD.

The purpose of this study is to conduct dynamic seat pressure mapping on vehicle seats during its operation on different test tracks under ambient environmental conditions for a defined speed. The test track comprises of pave roads, high frequency track, low frequency track and twist track. The variations in pressure distribution on seat during diverse road load inputs help to understand the seat cushion and back comfort for unique percentiles of human subjects ranging from 50th to 95th percentile population. For conducting the study, a sport utility vehicle (SUV) loaded with leatherette seats has chosen. Totally six participants (human subjects), five male and one female selected for the study based on their BMI (Body mass index) and body morphology. Pressure mats suitable for taking dynamic load inputs and able to log the data at a defined sampling rate mounted on seats and secured properly. The pressure mats should cover the seat cushion, bolster areas and back seat completely.

Construction equipment off highway vehicles are heavy industry vehicles that run on diesel engines. To meet the emission norms, these engines have the Exhaust After Treatment System (EATS) which includes two primary subassemblies, i.e., a Diesel Oxidation Catalyst (DOC) subassembly to reduce the HC and CO emissions and a Selective catalytic Reduction (SCR) subassembly to reduce NOx emissions. Because of the excessive vibrations in the engine and continuous heavy-duty usage of the Construction equipment, any failures in the EATS system leading to escape of exhaust gas is a statuary non-compliance. Hence, understanding the effect of engine vibrations and proposing a cost-effective solution is paramount in designing the EATS system including the SCR assembly. A field-testing failure of an SCR assembly has been taken in consideration for this study.

One of the key factors driving the automotive world is emission regulations. Zero emissions, clean engine concept are some buzz words being used extensively in the automotive industry. Stringent emission regulations throughout the world mean that automotive manufacturers have to pay attention to minimizing engine out emissions. Electronic engine management systems allow flexibility in controlling injection parameters & provide a means for optimizing engine performance. This paper presents work carried out on a 2.49L common rail direct injection diesel engine to achieve Euro IV emission targets. Without after-treatment devices, it is difficult for engine management alone to meet Euro IV and further stringent emissions. To overcome this, two type of after-treatment technologies are adopted by OEM's Selective Catalyst Reduction Diesel Particulate Filter Huge amount of research is being done on the application, cost aspect and availability of component samples for series production.

The effect of early post injection in diesel engine was studied with respect to engine out emissions and torque output. Initial tests indicated that there is significant reduction of soot for same NOx or with reduced NOx due to early Post Injection (POI) in traditional high speed diesel engine depending on various operating conditions. Further studies indicated that varying the post injection quantity and timing improved engine out NOx and soot emissions significantly and that the degree of this influence depends on speed and load of the engine. Additional investigations like study of heat release curve and air by fuel ratio were done to understand this effect completely.

The present work is concerned with the design of an optimum air intake system for a single cylinder reciprocating diesel engine. It is a well known fact that air flow rates of a naturally aspirated engine are sensitive to the geometrical dimensions of the pipes that connect the engine to the atmosphere. Hence, tuning intake system dimensions for optimum airflow rates is of great importance. In this scenario simulation tools can be useful for the optimization of intake system. The one dimensional simulation tool AVL BOOST is used to predict air flow rates with different combinations of connecting hose diameters and lengths. Subsequently air flow rates are measured with selected clean hoses on an engine steady state test bench. It is found in the initial tests that the lengths and diameters of optimum hoses deviate from the AVL BOOST predicted optimum geometric dimensions.

Closed crankcase ventilation prevent harmful gases from entering atmosphere thereby reducing hydrocarbon emissions. Ventilation system usually carries blowby gases along with oil mist generated from Engine to Air intake system. Major sources of blowby occurs from leak in combustion chamber through piston rings, leakage from turbocharger shafts & leakage from valve guides. Oil mist carried by these blowby gases gets separated using separation media before passing to Air Intake. Fleece separation media has high separation efficiency with lower pressure loss for oil aerosol particles having size above 10 microns. However, efficiency of fleece media drops drastically if size of aerosol particles are below 10 microns. Aerosol mist of lower particle size (>10 microns) generally forms due to flash boiling on piston under crown area and from shafts of turbo charger due to high speeds combined with elevated temperatures. High power density diesel engine is taken for our study.

Plenum is the part located between the front windshield and the bonnet of an automobile . It is primarily used as an air inlet to the HVAC during fresh air mode operation. It’s secondary functions include water drainage, aesthetic cover to hide the gap between windshield to bonnet, concealing wiper motors and mechanisms etc. The plenum consists mainly two sub parts viz. upper plenum and lower plenum. Conventional plenum design which is found in majority of global OEMs employ a plastic upper plenum and a metal lower plenum which spans across the entire width of engine compartment. This conventional lower plenum is bulky, consumes more packaging space and has more weight. In this paper, we propose a novel design for the plenum lower to overcome above mentioned limitations of the conventional design. This novel design employs a dry and wet box concept for its working and is made up of complete plastic material.

For ensuring environmental safety, strong emphasis on CO2 pollution reduction is mandated which led to evolution of miller cycle engines. However, the inherent Miller engine characteristic is the lower volumetric efficiency when compared to otto engines because of which small turbo chargers with variable geometry turbines are used to induct air into the engine. With miller engine and VGT turbo charger combination arises the challenges of charge controllability because of lower inertia and reduced vane control area. With conventional turbo charger control methods, the response time is slow thereby leading to turbo lag or severe over boosting, this is overcome by accurate engine modelling and using the same as input for charger control.

In automotive market, with competitive car prices, build quality of a car will be a major distinguishing factor. Consumer's need for acoustic comfort has evolved from the removal of annoying noises to perceived sound quality. Operational sounds from electromechanical systems like sunroof system, window regulator, door lock system, HVAC etc. directly interact with users’ senses. The perceived acoustics comfort of these sounds are direct indicators of vehicle character and can influence customer’s buying decision. With the reduction in product development time and stringent cost constraints, a proper structured target setting methodology to benchmark & evaluate these operational sounds is crucial. In this paper, such a target setting methodology is proposed and discussed for operational sound quality evaluation. Electromechanical noises from various vehicles are measured using binaural head measurement system.

Automotive manufacturers are constantly working towards enhancing the driving experience of the customers. In this context, improving the static and dynamic gear shift quality plays a major role in ensuring a pleasant and comfortable driving experience. Moreover, the gear shift quality of any manual transmission is mainly defined by the design of the synchronizer system. The synchronizer sleeve strut detent groove profile plays a vital role in defining the performance of the synchronizer system by generating the minimum required pre-synchronization force. This force is important to move the outer synchronizer ring (blocker ring) to the required index position and to wipe-out the oil from the conical friction surfaces to build rapid high cone torque. Both these functional requirements are extremely critical to have a smooth and quick synchronization of the rotating parts under dynamic shift conditions.

October 2010 has brought major change over in Indian Auto Industries, with all India going BS-III Emission compliant (Metro with BS-IV Emission norms). During that time majority of the utility segment vehicles were having diesel engine with simple mechanical fuel injection system. To make these vehicles BS-III compliance cost effectively, with same fuel economy and reliability, was a challenging task. To enable this, Exhaust Gas Recirculation (EGR) through simple pneumatic EGR valve was the optimum technique. The EGR valve was controlled by means of simple Electronic Control Unit (ECU). Limitations of mechanical diesel fuel injection pump, stringent emission regulations, coupled with production constraints and variations, calls for robust control logics for governing EGR. The present work describes the robust strategies and logics of intelligent EGR governing of a 2.5 l, four Cylinder turbocharged, mechanical pump diesel engine for a BS-III compliant multi utility vehicle.

In current scenario importance of fuel efficient vehicles, lesser emissions & energy efficiency are the major considerations for any vehicle manufacturer. To meet these expectations vehicle manufacturer are exploring alternate powertrains to reduce emissions and produce better fuel efficient vehicles. For any vehicle manufacturer component cost, weight and package volume are the major driving factors for success. This is even true for latest upcoming hybrid and electric vehicles as well. To gain advantage and introduce products faster, OEMs are inclined to electrify their existing platforms to compete with other manufacturers. To convert existing vehicles into hybrid vehicles, all the major components like e machine, High voltage battery, power electronics etc. needs to be carefully packaged along with existing components in the same package space.

The automotive industry is currently facing the challenge of significantly stringent requirements regarding CO₂ emission and fuel economy coming from both legislations and customer demand. Advanced engine technologies play a vital role for downsizing of gasoline engine. The development of key design technologies for high efficiency gasoline engines is required for the improvement of competitive power in the global automobile industry. This paper focused on effect of geometry of intake manifold of gas exchange process and consequently the performance of the engine. Specially, the optimal design technologies for the intake manifold and intake port shape must be established for high performance, increasingly stringent fuel economy and emission regulations. Space in vehicle or packaging constraints and cost are also important factors while consideration of the design.

In today's fast growing automobile world, the Emission limits are stringent; customer expectations of vehicle performance and Fuel economy are more. Achieving these parameters for the given engine are challenging task for any automobile engineers. BS4 Emission limits are 50% more stringent than BS3 limits and from April 2010 onwards, all passenger cars which will be selling in 13 metro cities in India should be BS4 emission compliant. In this paper, we have described how BS4 limits were achieved in a MPV with 2.49 l, 70kW Common Rail Direct Injection Turbocharged Diesel engine, with push rod. During Emission development, the following processes were followed to meet BS4 emission limits without sacrificing the engine performance, Fuel Economy and Noise. Selecting suitable hardwares like Turbocharger, EGR cooler at engine level to reduce NOx and Unburned Hydrocarbon Emissions with best Brake specific fuel consumption.